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So the engine went on the 6 last week. I told a few guys here about it but I thought I'd make a thread to show what happened. I'll be copying and pasting from a thread on another forum...

8/10/12

So the engine in my Mazda crapped out today. Not sure exactly what the cause is but I'll give a little back story...

Drove to work today (about 4.5 miles). Heard a clicking sound that sounded like an exhaust manifold leak. Didn't think too much of it because I know one of my manifolds IS leaking. Took my last turn and the oil light came on and the clicking turned to a loud wrapping noise. Engine shut down and I coasted into my parking lot. Didn't have a rag on me to clean off the dipstick to check oil. Pulled the dipstick anyway and found it was wet with oil but not as much as I think there should be. Checked oil later and found it barely reading on dipstick (about 4 quarts in engine, supposed to be 6). Drained oil and found some minor metal flakes. Changed oil filter and put some clean oil in her. Bumped the starter a few times just to try and move some oil around. Hit the starter to crank her and it didn't make it more than half of a revolution before suddenly stopping, kind of like it's mechanically seized up.

So now I've got to tear into is and figure out what the hell is going on in there.
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8/10/12

Just looked up my warranty. Ended 2.5 weeks ago.

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8/11/12

Cut the old filter open last night. The filter was doing its job. There was a lot of metal in it but it was all VERY fine stuff, like glitter.
Going to try beating the starter with a hammer to see if I jammed up the solenoid before pulling the pan today.

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8/11/12

Not the starter. Pulled the pan and found a bunch of metal in there. Looked up and found the #6 piston skirt broken. A piece of it was in the pan. I think it was my own fault too for a couple of reasons. I've had random misfires for a while now and haven't been able to fix it yet. Could have contributed to the problem. Also, the MSDS headers I put on have the O2 sensors on an odd place that I don't like. The primary sensors are only reading one cylinder each. I should have extended them and put them in a spot that rear each entire bank. I'm thinking that if cylinder #4 was reading rich, it would have leaned out the whole bank. I guess it's just theory but that's what I'm thinking right now.

I guess it's time I find out why the jeep is overheating. And also to fix the exhaust on it.

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8/11/12

Well a couple months ago I picked up a spare engine from Justin (The Great NY) in NY. Was told it had a lot of blow-by but it was running when removed. I'll be rebuilding that and swapping it in.


Had a busy afternoon. Picked up an engine stand, "fixed" the exhaust in the jeep (which means I cut off the rotted muffler and tail pipe, and used a hose clamp to get the remaining pipe up off the crossmember). And tried to put the engine on the stand.

Went to put the spare engine on the stand and realized that I can't mount it the normal way because it doesn't have a normal block. Instead of having main caps for the crank, it's got one whole piece that is bolted to the bottom of the block (between block and oil pan). So If I were to bolt the engine stand plate to it, I wouldn't be able to remove that bottom part of the block. The factory tool is an adapter that bolts to the side of the block and to the engine stand plate.

So I took the engine and stand to my dad's shop and he made me up one (SST#fordcansuckit). Now I'm just letting the paint dry overnight before bolting it up and getting the engine on the stand tomorrow. I'd like to get the heads off and stripped so I can send them to the machine shop on Monday to have them checked.

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8/12/12

Got some stuff done today. Man-handled the engine onto my engine stand and got it torn down. Heads are off and stripped. I'll be calling the machine shop tomorrow to have them checked over. Got everything else off the engine and left just the block and rotating assembly together. I'll get those apart another day, probably next weekend. I took some pics of the process, which I'll post up later.
 

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Discussion Starter #7
8/15/12

Just got the call from the machine shop. Said they found some metal in the heads. Nothing big, kind of like never-seize. He said it wore out the valves though. So it just needs valves and seals and they're good heads again. He said it'll cost me $275 plus the valves and seals for everything he's got into it so far and for installing the new stuff. I forgot to check on doing a quick port job while they have it.

I'm not in a huge rush to get everything done anymore though. The more I think about it, the more I feel like this is a good opportunity to build this motor so I don't have to swap another one in later. Got to save up some cash for my rods and pistons now. Just gotta hope nothing happens to the Jeep. (There's gotta be some wood to knock on around here...)
 

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Damn. Sorry to hear about that the dreaded V6 curse has hit you. IMO it's a great idea to build it up while it's out. Someone else on this board needs to give Justin some competition... :)

Still planning to have the shop port the heads?
 

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Discussion Starter #10
Damn. Sorry to hear about that the dreaded V6 curse has hit you. IMO it's a great idea to build it up while it's out. Someone else on this board needs to give Justin some competition... :)

Still planning to have the shop port the heads?
Probably. I can't see not doing it since it's apart now anyway. It'll be a slow process though because this is gonna take more cash than I have right now.
 

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Wow lots of work to get done Andy. Good luck with all of this.

Also, for moar cash just make moar stickers :D jk
 

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Discussion Starter #13
Well I did some machine shop shopping. I found a machine shop that is more performance oriented and even has the correct torque plate for my block. He recently did a nice build on a Noble (same block) engine.

I pulled my heads out of the other shop and will have this new shop go through them later. For now, I brought my block to this new machine shop to be gone through. He'll thoroughly clean everything, inspect the crank (which I think is fine but I haven't seen under the mains yet), and inspect and measure everything else. Then he'll give me a spec sheet so I know what size parts to order later.

I still have to get back over there to measure up my head bolt and main bolt holes in the block. ARP doesn't have a listing for this engine so they sent me a sheet to fill out so they can get me some studs. I've got the heads all measured up already. I also need to buy the head gasket set so I can measure the thickness of the gasket.

All of this needs to happen before the machine shop can torque the torque plate down properly. They can't machine or hone the cylinders until they can get the torque plate on properly and they need the exact hardware I'm going to use.
 

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Discussion Starter #15
damn i was wondering if only the speed3,6 were the only ones with all this bad lock of seized engines and zoom, zoom, BOOM... g/l with the build.
Typically the v6 engines are pretty solid. I'm not sure exactly what happened but I'll be doing some failure analysis on the old engine after I swap the new engine in.
 

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Thanks for sharing and sorry to see the 6 is costing you. Does it not have a knock sensor? I would think that even if it went lean (based on a sample of one hole) the knock sensor would retard the timing, but I'm a newby and don't even know where it is much less if it has one. Ask me about Yoders, I know them!

Broken skirts are often from too much bore clearance. Add heat from detonation and high RPM and snap. Can you post a hi-res pic of the piston? I'd be curious to know the bore dia vs spec and same for the piston. IIRC I saw the pistons are bushed so it seems unlikely the wrist pin seized. Where is the other thread you're updating?
So where did all that metal come from if its just a busted skirt? Something else gave its life I'd suspect.

Good effort, Keep it Up! :thumbup:
 

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Discussion Starter #17
I'd imagine the metal came from bearings. I believe it does have a knock sensor but don't quote me on that. I didn't hear any detonation at all so I'm really not sure about it going lean, was just putting that out there.

The other thread is on my local forum at NEMotorSport Forums. You might need to sign up to see it though. I'm zoom6 over there.

EDIT: Also, I haven't pulled the engine out of the car yet. I'm waiting to get the other engine ready to go in first.
 

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Discussion Starter #19
Are you gonna put turbo on? Any upgrades to the new engine?
Got this little guy sitting brand new in a box waiting to go on.



Twin scroll GT35R. :D

Planning forged pistons and rods. Dropping the compression ratio down to 8.5:1 to run higher boost. And some minor p&p for the heads. Maybe stainless valves if I can swing it.
 
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